Genome-wide association studies and Mendelian randomization analyses provide insights into the causes of early-onset colorectal cancer

BACKGROUND

The incidence of early-onset colorectal cancer (EOCRC; diagnosed <50 years of age) is rising globally; however, the causes underlying this trend are largely unknown. CRC has strong genetic and environmental determinants, yet common genetic variants and causal modifiable risk factors underlying EOCRC are unknown. We conducted the first EOCRC-specific genome-wide association study (GWAS) and Mendelian randomization (MR) analyses to explore germline genetic and causal modifiable risk factors associated with EOCRC.

PATIENTS AND METHODS

We conducted a GWAS meta-analysis of 6176 EOCRC cases and 65 829 controls from the Genetics and Epidemiology of Colorectal Cancer Consortium (GECCO), the Colorectal Transdisciplinary Study (CORECT), the Colon Cancer Family Registry (CCFR), and the UK Biobank. We then used the EOCRC GWAS to investigate 28 modifiable risk factors using two-sample MR.

RESULTS

We found two novel risk loci for EOCRC at 1p34.1 and 4p15.33, which were not previously associated with CRC risk. We identified a deleterious coding variant (rs36053993, G396D) at polyposis-associated DNA repair gene MUTYH (odds ratio 1.80, 95% confidence interval 1.47-2.22) but show that most of the common genetic susceptibility was from noncoding signals enriched in epigenetic markers present in gastrointestinal tract cells. We identified new EOCRC-susceptibility genes, and in addition to pathways such as transforming growth factor (TGF) β, suppressor of Mothers Against Decapentaplegic (SMAD), bone morphogenetic protein (BMP) and phosphatidylinositol kinase (PI3K) signaling, our study highlights a role for insulin signaling and immune/infection-related pathways in EOCRC. In our MR analyses, we found novel evidence of probable causal associations for higher levels of body size and metabolic factors-such as body fat percentage, waist circumference, waist-to-hip ratio, basal metabolic rate, and fasting insulin-higher alcohol drinking, and lower education attainment with increased EOCRC risk.

CONCLUSIONS

Our novel findings indicate inherited susceptibility to EOCRC and suggest modifiable lifestyle and metabolic targets that could also be used to risk-stratify individuals for personalized screening strategies or other interventions.

First Measurement of the Nuclear-Recoil Ionization Yield in Silicon at 100 eV

We measured the nuclear-recoil ionization yield in silicon with a cryogenic phonon-sensitive gram-scale detector. Neutrons from a monoenergetic beam scatter off of the silicon nuclei at angles corresponding to energy depositions from 4 keV down to 100 eV, the lowest energy probed so far. The results show no sign of an ionization production threshold above 100 eV. These results call for further investigation of the ionization yield theory and a comprehensive determination of the detector response function at energies below the keV scale.

Constraints on Lightly Ionizing Particles from CDMSlite

The Cryogenic Dark Matter Search low ionization threshold experiment (CDMSlite) achieved efficient detection of very small recoil energies in its germanium target, resulting in sensitivity to lightly ionizing particles (LIPs) in a previously unexplored region of charge, mass, and velocity parameter space. We report first direct-detection limits calculated using the optimum interval method on the vertical intensity of cosmogenically produced LIPs with an electric charge smaller than e/(3×10^{5}), as well as the strongest limits for charge ≤e/160, with a minimum vertical intensity of 1.36×10^{-7}  cm^{-2} s^{-1} sr^{-1} at charge e/160. These results apply over a wide range of LIP masses (5  MeV/c^{2} to 100  TeV/c^{2}) and cover a wide range of βγ values (0.1-10^{6}), thus excluding nonrelativistic LIPs with βγ as small as 0.1 for the first time.

Light Dark Matter Search with a High-Resolution Athermal Phonon Detector Operated above Ground

We present limits on spin-independent dark matter-nucleon interactions using a 10.6 g Si athermal phonon detector with a baseline energy resolution of σ_{E}=3.86±0.04(stat)_{-0.00}^{+0.19}(syst)  eV. This exclusion analysis sets the most stringent dark matter-nucleon scattering cross-section limits achieved by a cryogenic detector for dark matter particle masses from 93 to 140  MeV/c^{2}, with a raw exposure of 9.9 g d acquired at an above-ground facility. This work illustrates the scientific potential of detectors with athermal phonon sensors with eV-scale energy resolution for future dark matter searches.

Standardization of Temporal Bone CT Planes across a Multisite Academic Institution

BACKGROUND AND PURPOSE

Variable head positioning in the CT gantry results in variable and inconsistent temporal bone imaging planes. Our aim was to evaluate whether an automated postprocessing algorithm or an educational intervention with postprocessing by a technologist could result in consistent temporal bone image reformations into planes referenced to the lateral semicircular canal.

MATERIALS AND METHODS

Instructions to reformat small-FOV images in planes referenced to the lateral semicircular canal were posted at 12 CT scanner consoles and e-mailed to 65 CT technologists at a single multisite institution. Automated reformatted images were also produced. The angles between the technologist- and automated-reformatted axial image planes and lateral semicircular canal planes were measured. Group differences were calculated with Mann-Whitney-Wilcoxon tests. Differences in homogeneity of variances were calculated with Fligner-Killeen tests.

RESULTS

Two hundred ten temporal bones were imaged in 4 months following the intervention. Reformats by technologists were accurate in 87% of the axial and 81% of the coronal planes, with a trend toward improvement with time. Eighty percent of incorrectly reformatted images occurred at off-site, inpatient, and emergency department scanners. The error angle was significantly lower for technologist-reformatted images (median, 4.9°) than for acquisition plane images (median, 14.6°; P = 3 × 10^-14) or automated-reformatted images (median, 13.8°; P = 9 × 10^-13). The angle error variance was significantly more homogeneous for technologist-reformatted images (P = 3 × 10^-8) and automated-reformatted images (P = 1 × 10^-5) than for acquisition plane images.

CONCLUSIONS

Both technologist and automated reformatting of temporal bone images resulted in significantly less imaging plane variance compared with images reformatted in the acquisition plane, but reformatting by technologists remains necessary at our institution given our preference for standardized planes referencing the lateral semicircular canals.

Erratum: First Dark Matter Constraints from a SuperCDMS Single-Charge Sensitive Detector [Phys. Rev. Lett. 121, 051301 (2018)]

This corrects the article DOI: 10.1103/PhysRevLett.121.051301.

First Dark Matter Constraints from a SuperCDMS Single-Charge Sensitive Detector

We present the first limits on inelastic electron-scattering dark matter and dark photon absorption using a prototype SuperCDMS detector having a charge resolution of 0.1 electron-hole pairs (CDMS HVeV, a 0.93 g CDMS high-voltage device). These electron-recoil limits significantly improve experimental constraints on dark matter particles with masses as low as 1  MeV/c^{2}. We demonstrate a sensitivity to dark photons competitive with other leading approaches but using substantially less exposure (0.49 g d). These results demonstrate the scientific potential of phonon-mediated semiconductor detectors that are sensitive to single electronic excitations.

Results from the Super Cryogenic Dark Matter Search Experiment at Soudan

We report the result of a blinded search for weakly interacting massive particles (WIMPs) using the majority of the SuperCDMS Soudan data set. With an exposure of 1690 kg d, a single candidate event is observed, consistent with expected backgrounds. This analysis (combined with previous Ge results) sets an upper limit on the spin-independent WIMP-nucleon cross section of 1.4×10^{-44} (1.0×10^{-44})  cm^{2} at 46  GeV/c^{2}. These results set the strongest limits for WIMP-germanium-nucleus interactions for masses >12  GeV/c^{2}.

Long-term survival outcomes of triple-receptor negative breast cancer survivors who are disease free at 5 years and relationship with low hormone receptor positivity

Background:

We counsel our triple-negative breast cancer (TNBC) patients that the risk of recurrence is highest in the first 5 years after diagnosis. However, there are limited data with extended follow-up on the frequency, characteristics, and predictors of late events.

Methods:

We queried the MD Anderson Breast Cancer Management System database to identify patients with stage I–III TNBC who were disease free at 5 years from diagnosis. The Kaplan–Meier method was used to estimate yearly recurrence-free interval (RFI), recurrence-free survival (RFS), and distant relapse-free survival (DRFS), as defined by the STEEP criteria. Cox proportional hazards model was used to compute hazard ratios (HRs) and 95% confidence intervals (CIs).

Results:

We identified 873 patients who were disease free at least 5 years from diagnosis with median follow-up of 8.3 years. The 10-year RFI was 97%, RFS 91%, and DRFS 92% the 15-year RFI was 95%, RFS 83%, and DRFS 84%. On a subset of patients with oestrogen receptor and progesterone receptor percentage recorded, low hormone receptor positivity conferred higher risk of late events on multivariable analysis for RFS only (RFI: HR=1.98, 95% CI=0.70–5.62, P-value=0.200; RFS: HR=1.94, 95% CI=1.05–3.56, P-value=0.034; DRFS: HR=1.72, 95% CI=0.92–3.24, P-value=0.091).

Conclusions:

The TNBC survivors who have been disease free for 5 years have a low probability of experiencing recurrence over the subsequent 10 years. Patients with low hormone receptor-positive cancers may have a higher risk of late events as measured by RFS but not by RFI or DRFS.

Abstract P6-09-35: Proposal for a new breast cancer staging classification: Incorporating clinical and biologic factors

Background: The current breast cancer staging system, based on anatomy, does not always reflect the variable clinical course outcomes seen in the clinic. Other important and known determinants of prognosis and survival in breast cancer are age, grade, and receptor subtypes. In this analysis, we sought to demonstrate that these additional factors were important determinants of breast cancer specific and overall survival with an intention to propose a new staging classification. Methods: Through a prospectively maintained electronic database at the University of Texas MD Anderson Cancer Center, we identified patients with newly diagnosed invasive breast cancer, stage I-IV, who received surgery as an initial treatment from 1997 to 2014. Data points for the earliest invasive breast cancer event were recorded: age, pathologic stage (7th edition AJCC), grade, ER status, PR status, HER2-neu status, adjuvant treatment history, and outcomes (breast cancer-specific survival [BCSS] and overall survival [OS]). Cox proportional hazards model was used for the statistical analysis. Results: Of 22,131 patients, 99% were women in the following age groups (median age at surgery, 53 years [range, 16-98 years]): age &lt; 40 (13%), 40-69 (76%), &gt;70 (11%). Pathologic stages were: I: 50%, II: 39%, III: 9% and IV: 2%; 768 (3.5%) patients had bilateral breast cancer. Biological subtypes were as follows: Triple-negative (TN): 6%, Hormone receptor-positive/HER2-negative (HR+/HER2-): 70%, HER2-positive (HER2+): 24% (HR+, 9%; HR- 15%). Median follow-up was 7.9 years (95% CI, 7.8-8.0). In multivariate Cox regression modeling, age, grade, and clinical biomarker-based subtypes were significantly associated with breast cancer specific survival (BCSS).

Table 1. Breast cancer specific-survival: Multivariate modelCovariateLevelHR95% CI (p value)Overall p valueAge at DiagnosisLess than 401.521.37-1.68 (&lt;.0001) 40-69Reference&lt;.0001 70-791.050.89-1.24 (0.55) Over 801.150.79-1.66 (0.47)Pathologic StageIAReference&lt;.0001 IIB0.880.58-1.32 (0.54) IIA2.201.96-2.46 (&lt;.0001) IIB3.453.06-3.89 (&lt;.0001) IIIA4.293.70-4.96 (&lt;.0001) IIIB3.432.45-4.79 (&lt;.0001) IIIC6.585.52-7.84 (&lt;.0001) IV15.1212.72-17.96 (&lt;.0001)Biologic SubtypeHR+, HER2-Reference&lt;.0001 HR+, HER2+*0.580.46-0.73 (&lt;.0001) HR-, HER2+*1.100.90-1.35 (0.35) TN**2.001.82-2.21 (&lt;.0001)Nuclear GradeIReference&lt;.0001 II1.731.34-2.23 (&lt;.0001) III3.292.55-4.24 (&lt;.0001)*All patients were treated with trastuzumab in the adjuvant setting **Considering TN as the reference (HR (95% CI): HR+/HER2- (0.50 (0.45-0.55)), HR+/HER2+ (0.29 (0.23-0.37)), HR-/HER2+ (0.55(0.45-0.68). Abbreviations - BCSS: HR: hazard ratio, CI: confidence interval, HR+: hormone receptor positive, HR-: hormone receptor negative, HER2+: Her2-neu positive, HER2-: HER2-neu negative, TN: triple negative, Reference: 1.00

Conclusion: More individualized prediction of outcomes for breast cancer is possible by considering clinical and biologic characteristics in addition to anatomic stage. We intend to integrate pathologic stage, age, and biologic factors into a novel prognostic model to propose a new staging classification for breast cancer.

Citation Format: Murthy RK, Song J, Raghavendra AS, Li Y, Hsu L, Barcenas CH, Tripathy D, Berry D, Hortobagyi GN. Proposal for a new breast cancer staging classification: Incorporating clinical and biologic factors [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P6-09-35.

Abstract P3-10-07: Impact of enrollment in clinical trials on survival of metastatic breast cancer patients

Background: The number of patients worldwide with metastatic breast cancer (MBC) who participate in therapeutic clinical trials has remained so far low. One of the reasons is a lack of opportunity, whereas another is fear of health care providers and patients of poor outcome of the use of new drugs. We therefore investigated whether survival in patients with MBC who participated in first-line therapeutic clinical trials is worse than that in patients who received only standard care and never enrolled in a clinical trial. We hypothesized that first-line therapeutic clinical trials do not negatively affect survival outcome. Methods: We reviewed the records of 5501 patients with MBC treated at The University of Texas MD Anderson Cancer Center from January 2000 to December 2010. We extracted a first cohort of 285 patients enrolled in a therapeutic clinical trial for the first time for first-line systemic MBC treatment. The second cohort, referred to as the eligible control population, consisted of 367 patients without comorbidities who did not participate in a clinical trial at any stage of their disease; these patients lived in Harris County, in which MD Anderson is located, and thus could be potentially eligible for MD Anderson's financial assistance program. To limit confounding factors, we excluded male patients and patients with known brain metastasis from both cohorts. Results: The median follow-up duration in our cohort was 7.16 years (95% confidence interval [CI], 6.53-7.64 years). We observed discrepancies in race (minorities were less represented in the clinical trial arm), estrogen receptor (ER) status (more ER-positive than ER-negative patients participated in clinical trials), and metastatic disease site (fewer patients with bone metastasis participated in clinical trials) between the two groups. Overall, we observed no significant differences in progression-free survival (PFS) or overall survival (OS) duration between the treatment arms. Specifically, in the clinical trial cohort, the median PFS duration was 7.00 months (95% CI, 5.72-8.71 months), and the median OS duration was 28.48 months (95% CI, 22.70-34.60 months). In the control cohort, the median PFS duration was 10.02 months (95% CI, 7.13-11.99 months), and the median OS duration was 28.71 months (95% CI, 24.41-31.31 months) (P = .089 and .335, respectively). Conclusion: In MBC patients, enrolling in first-line therapeutic clinical trials does not result in worse survival than does never enrolling in a clinical trial. This study should reassure health care providers in demonstrating that enrollment in a clinical trial does not negatively affect survival in MBC patients.

Citation Format: Le Du F, FUJII T, Park M, Liu D, Hsu L, Gonzalez-Angulo A-M, Ueno NT. Impact of enrollment in clinical trials on survival of metastatic breast cancer patients [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P3-10-07.

Effect of aerobic exercise on cancer-associated cognitive impairment: A proof-of-concept RCT

BACKGROUND

Change in cognitive ability is a commonly reported adverse effect by breast cancer survivors. The underlying etiology of cognitive complaints is unclear and to date, there is limited evidence for effective intervention strategies. Exercise has been shown to improve cognitive function in older adults and animal models treated with chemotherapy. This proof-of-concept randomized controlled trial tested the effect of aerobic exercise versus usual lifestyle on cognitive function in postmenopausal breast cancer survivors.

METHODS

Women, aged 40 to 65 years, postmenopausal, stages I to IIIA breast cancer, and who self-reported cognitive dysfunction following chemotherapy treatment, were recruited and randomized to a 24-week aerobic exercise intervention (EX; n = 10) or usual lifestyle control (CON; n = 9). Participants completed self-report measures of the impact of cognitive issues on quality of life (Functional Assessment of Cancer Therapy-Cognitive version 3), objective neuropsychological testing, and functional magnetic resonance imaging at baseline and 24 weeks.

RESULTS

Compared to CON, EX had a reduced time to complete a processing speed test (trail making test-A) (-14.2 seconds, P < .01; effect size 0.35). Compared to CON, there was no improvement in self-reported cognitive function and effect sizes were small. Interestingly, lack of between-group differences in Stroop behavioral performance was accompanied by functional changes in several brain regions of interest in EX compared to CON at 24 weeks.

CONCLUSION

These findings provide preliminary proof-of-concept results for the potential of aerobic exercise to improve cancer-related cognitive impairment and will serve to inform the development of future trials.

Radiographic failure and rates of re-operation after acromioclavicular joint reconstruction: a comparison of surgical techniques

AIMS

To compare radiographic failure and re-operation rates of anatomical coracoclavicular (CC) ligament reconstructional techniques with non-anatomical techniques after chronic high grade acromioclavicular (AC) joint injuries.

PATIENTS AND METHODS

We reviewed chronic AC joint reconstructions within a region-wide healthcare system to identify surgical technique, complications, radiographic failure and re-operations. Procedures fell into four categories: (1) modified Weaver-Dunn, (2) allograft fixed through coracoid and clavicular tunnels, (3) allograft loop coracoclavicular fixation, and (4) combined allograft loop and synthetic cortical button fixation. Among 167 patients (mean age 38.1 years, (standard deviation (sd) 14.7) treated at least a four week interval after injury, 154 had post-operative radiographs available for analysis.

RESULTS

Radiographic failure occurred in 33/154 cases (21.4%), with the lowest rate in Technique 4 (2/42 4.8%, p = 0.001). Half the failures occurred by six weeks, and the Kaplan-Meier survivorship at 24 months was 94.4% (95% confidence interval (CI) 79.6 to 98.6) for Technique 4 and 69.9% (95% CI 59.4 to 78.3) for the other techniques when combined. In multivariable survival analysis, Technique 4 had better survival than other techniques (Hazard Ratio 0.162, 95% CI 0.039 to 0.068, p = 0.013). Among 155 patients with a minimum of six months post-operative insurance coverage, re-operation occurred in 9.7% (15 patients). However, in multivariable logistic regression, Technique 4 did not reach a statistically significant lower risk for re-operation (odds ratio 0.254, 95% CI 0.05 to 1.3, p = 0.11).

CONCLUSION

In this retrospective series, anatomical CC ligament reconstruction using combined synthetic cortical button and allograft loop fixation had the lowest rate of radiographic failure.

TAKE HOME MESSAGE

Anatomical coracoclavicular ligament reconstruction using combined synthetic cortical button and allograft loop fixation had the lowest rate of radiographic failure.

New Results from the Search for Low-Mass Weakly Interacting Massive Particles with the CDMS Low Ionization Threshold Experiment

The CDMS low ionization threshold experiment (CDMSlite) uses cryogenic germanium detectors operated at a relatively high bias voltage to amplify the phonon signal in the search for weakly interacting massive particles (WIMPs). Results are presented from the second CDMSlite run with an exposure of 70 kg day, which reached an energy threshold for electron recoils as low as 56 eV. A fiducialization cut reduces backgrounds below those previously reported by CDMSlite. New parameter space for the WIMP-nucleon spin-independent cross section is excluded for WIMP masses between 1.6 and 5.5  GeV/c^{2}.

Abstract P5-01-02: Multimodality molecular imaging with dynamic 18F-fluorodeoxyglucose positron emission tomography (FDG PET) and MRI to evaluate response and resistance to neoadjuvant chemotherapy (NAC)

Background: Using quantitative FDG PET to measure glucose metabolism and perfusion, and dynamic contrast-enhanced (DCE) MRI to measure perfusion, we previously identified a metabolic signature for breast cancer resistant to NAC. This imaging signature is (1) persistent or increased tumor perfusion despite treatment, (2) an altered pattern of glucose kinetics in response to therapy, and (3) pre-therapy mismatch between tumor metabolism (MRFDG) and glucose delivery (K1) (high ratio of MRFDG/K1). These patterns predict poor response, early relapse and death independent of established prognostic factors, including pathologic response. Identification of factors associated with resistance or response to therapy is the translational goal of "Quantitative Dynamic PET and MRI in Breast Cancer Therapy," part of the Seattle Breast SPORE (1P50CA138293).

Methods: Patients (Pts) undergoing NAC for histologically confirmed breast cancer (stage II-III) were approached for this trial (CCIRB# 7587). FDG PET and DCE-MRI were obtained pre-therapy, 2-12 weeks after start of NAC (mid-therapy) and after completion of NAC. Breast biopsies were obtained pre-therapy and post-NAC. FDG PET included a dynamic scan with kinetic analysis. PET measures included SUVmax, MRFDG, K1, Ki, and Patlak. 3T DCE-MRI measurements included semi-quantitative vascular parameters of peak enhancement (PE), signal enhancement ratio (SER), washout fraction, functional tumor volume, and apparent diffusion coefficient (ADC) from diffusion-weighted MRI (DWI). Breast biopsies were assayed by immunohistochemistry and gene expression profiling. NAC was per physician's choice with most pts receiving weekly paclitaxel (with trastuzumab if HER2+) followed by doxorubicin/cyclophosphamide.

Results: 32 pts have completed the study. Pathologic complete response (pCR), defined as absence of invasive cancer in the breast, was observed in 9 (28%); near pCR defined as only microscopic residual invasive cancer in 3 (9%) more pts. Mid-therapy decline in SUVmax and K1 was associated with near pCR; (p-value 0.06, 0.04, respectively). Pre-therapy PET measures of MRFDG and K1 were not predictive of pCR. On MRI, pre-therapy PE (p=0.009), SER (p=0.01), washout fraction (p=0.02), ADC (p=0.08, trend) and mid-therapy change in volume (p=0.05) were each predictive of pCR. Gene profiling of pre-therapy biopsies showed correlation between high MRFDG/K1 ratio in basal and luminal B tumors.

Conclusions: Assessment of serial changes in tumor metabolism and perfusion by FDG PET and DCE-MRI is feasible in the clinic. Mid-therapy decline in metabolism and glucose delivery was predictive of pCR; consistent with prior retrospective series. Baseline DCE-MRI and DWI measures show promise to predict response, and associations of mid-therapy change in MR functional tumor volume with pCR agree with findings of another multisite clinical trial (ISPY). These imaging parameters may serve as useful biomarkers to inform future neoadjuvant trials. Integration of imaging data with gene expression profiling revealed that the pattern of metabolism in luminal B tumors was closer to that of the basal subtype compared to other ER-positive tumors.

Citation Format: Specht JM, Partridge S, Chai X, Novakova A, Peterson L, Shields A, Guenthoer J, Linden HM, Gralow JR, Gadi V, Korde L, Hills D, Hsu L, Hockenbery DM, Kinahan P, Mankoff DA, Porter PL. Multimodality molecular imaging with dynamic 18F-fluorodeoxyglucose positron emission tomography (FDG PET) and MRI to evaluate response and resistance to neoadjuvant chemotherapy (NAC). [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P5-01-02.

Validation of multisociety combined task force definitions of abnormal disk morphology

BACKGROUND AND PURPOSE

The multisociety task force descriptively defined abnormal lumbar disk morphology. We aimed to use their definitions to provide a higher level of evidence for the validation of MR imaging in the evaluation of this pathology in patients who have undergone diskectomy by retrospectively classifying their preoperative MRI.

MATERIALS AND METHODS

This retrospective, institutional review board-approved study included 54 of 86 consecutive patients (47 men; average age, 44 years) enrolled in an ongoing prospective trial of surgically treated lumbar disk herniation who had preoperative MRI and documented intraoperative classification of the abnormal disk as protrusion, extrusion, or sequestration by the treating surgeon. Preoperative MRI was classified by 2 blinded radiologists; discrepancies were resolved by a third reader. Statistical analysis of interobserver agreement and imaging compared with surgical findings was performed.

RESULTS

The readers disagreed on only 1 of the 54 cases. The third reader resolved the disagreement. Eight protrusions and 46 extrusions were found on imaging, with no sequestrations. At surgery, there were 13 protrusions and 40 extrusions, with 2 of the extrusions also containing sequestrations; the remaining case had only sequestration. There were 16 discrepancies between imaging and surgery, resulting in 70% agreement.

CONCLUSIONS

This study, which was intended to validate the multisociety combined task force definitions of abnormal disk morphology by using MR imaging with a surgical criterion standard, found 70% agreement between imaging diagnosis and surgical findings. Although reasonable, this finding highlights differences that often exist between intraoperative and preoperative imaging findings of lumbar disk herniation.

First direct limits on lightly ionizing particles with electric charge less than e/6

While the standard model of particle physics does not include free particles with fractional charge, experimental searches have not ruled out their existence. We report results from the Cryogenic Dark Matter Search (CDMS II) experiment that give the first direct-detection limits for cosmogenically produced relativistic particles with electric charge lower than e/6. A search for tracks in the six stacked detectors of each of two of the CDMS II towers finds no candidates, thereby excluding new parameter space for particles with electric charges between e/6 and e/200.

Search for low-mass weakly interacting massive particles with SuperCDMS

We report a first search for weakly interacting massive particles (WIMPs) using the background rejection capabilities of SuperCDMS. An exposure of 577 kg days was analyzed for WIMPs with mass <30  GeV/c(2), with the signal region blinded. Eleven events were observed after unblinding. We set an upper limit on the spin-independent WIMP-nucleon cross section of 1.2×10(-42)  cm(2) at 8  GeV/c(2). This result is in tension with WIMP interpretations of recent experiments and probes new parameter space for WIMP-nucleon scattering for WIMP masses <6  GeV/c(2).

Search for low-mass weakly interacting massive particles using voltage-assisted calorimetric ionization detection in the SuperCDMS experiment

SuperCDMS is an experiment designed to directly detect weakly interacting massive particles (WIMPs), a favored candidate for dark matter ubiquitous in the Universe. In this Letter, we present WIMP-search results using a calorimetric technique we call CDMSlite, which relies on voltage-assisted Luke-Neganov amplification of the ionization energy deposited by particle interactions. The data were collected with a single 0.6 kg germanium detector running for ten live days at the Soudan Underground Laboratory. A low energy threshold of 170  eVee (electron equivalent) was obtained, which allows us to constrain new WIMP-nucleon spin-independent parameter space for WIMP masses below 6  GeV/c2.

Silicon detector dark matter results from the final exposure of CDMS II

We report results of a search for weakly interacting massive particles (WIMPS) with the silicon detectors of the CDMS II experiment. This blind analysis of 140.2 kg day of data taken between July 2007 and September 2008 revealed three WIMP-candidate events with a surface-event background estimate of 0.41(-0.08)(+0.20)(stat)(-0.24)(+0.28)(syst). Other known backgrounds from neutrons and 206Pb are limited to <0.13 and <0.08 events at the 90% confidence level, respectively. The exposure of this analysis is equivalent to 23.4 kg day for a recoil energy range of 7-100 keV for a WIMP of mass 10  GeV/c2. The probability that the known backgrounds would produce three or more events in the signal region is 5.4%. A profile likelihood ratio test of the three events that includes the measured recoil energies gives a 0.19% probability for the known-background-only hypothesis when tested against the alternative WIMP+background hypothesis. The highest likelihood occurs for a WIMP mass of 8.6  GeV/c2 and WIMP-nucleon cross section of 1.9×10(-41)  cm2.

Long-term treatment efficacy in primary inflammatory breast cancer by hormonal receptor- and HER2-defined subtypes

BACKGROUND

Subtypes defined by hormonal receptor (HR) and HER2 status have not been well studied in inflammatory breast cancer (IBC). We characterized clinical parameters and long-term outcomes, and compared pathological complete response (pCR) rates by HR/HER2 subtype in a large IBC patient population. We also compared disease-free survival (DFS) and overall survival (OS) between IBC patients who received targeted therapies (anti-hormonal, anti-HER2) and those who did not.

PATIENTS AND METHODS

We retrospectively reviewed the records of patients diagnosed with IBC and treated at MD Anderson Cancer Center from January 1989 to January 2011. Of those, 527 patients had received neoadjuvant chemotherapy and had available information on estrogen receptor (ER), progesterone receptor (PR), and HER2 status. HR status was considered positive if either ER or PR status was positive. Using the Kaplan-Meier method, we estimated median DFS and OS durations from the time of definitive surgery. Using the Cox proportional hazards regression model, we determined the effect of prognostic factors on DFS and OS. Results were compared by subtype.

RESULTS

The overall pCR rate in stage III IBC was 15.2%, with the HR-positive/HER2-negative subtype showing the lowest rate (7.5%) and the HR-negative/HER2-positive subtype, the highest (30.6%). The HR-negative, HER2-negative subtype (triple-negative breast cancer, TNBC) had the worst survival rate. HR-positive disease, irrespective of HER2 status, had poor prognosis that did not differ from that of the HR-negative/HER2-positive subtype with regard to OS or DFS. Achieving pCR, no evidence of vascular invasion, non-TNBC, adjuvant hormonal therapy, and radiotherapy were associated with longer DFS and OS.

CONCLUSIONS

Hormone receptor and HER2 molecular subtypes had limited predictive and prognostic power in our IBC population. All molecular subtypes of IBC had a poor prognosis. HR-positive status did not necessarily confer a good prognosis. For all IBC subtypes, novel, specific treatment strategies are needed in the neoadjuvant and adjuvant settings.

Abstract P3-10-05: Response to neoadjuvant systemic therapy (NST) in inflammatory breast cancer (IBC) according to estrogen receptor (ER) and HER2 expression

Background: Inflammatory breast cancer (IBC) is the most aggressive form breast cancer. NST, followed by local therapy (surgery and radiation therapy), is considered the current standard therapy for IBC. Among noninflammatory breast cancers, sensitivity to NST differs based on ER and HER2 status. However, whether the sensitivity to NST also differs in primary IBC based on ER status or other prognostic factors has not been studied in a large cohort.

Methods: We retrospectively reviewed 1078 patients (pts) newly diagnosed with IBC from April 1989 to January 2011. Of these, 838 pts met our inclusion criterion of stage III disease at diagnosis, and 713 of these pts had received NST and surgery. Among this population, 545 pts had information available on both ER and HER2 status. We compared pathological complete response (pCR) rates (defined as no evidence of invasive disease in the breast and ipsilateral axillary limph nodes) and clinical characteristics between ER and HER2-status subgroups and analyzed their clinical outcome. We used the Kaplan-Meier method to estimate the median recurrence-free survival (RFS) after surgery and overall survival (OS), and the Cox proportional hazards regression model to test the statistical significance of potential prognostic factors in each group.

Results: Overall 177 pts had ER+HER2− tumors; 75, ER+HER2+; 134, ER-HER2+; and 159, ER-HER2−. NST consisted of anthracycline-based [A] alone, a taxane [T] alone or with A+T; HER2 targeting therapies (H) were administered to 117 patients with HER2-positive breast cancer after 1998. Overall pCR rate was 14.7%. pCR rates are shown by marker subtype and NST received in the table below. pCR rate, nuclear grade, vascular invasion, clinical response to NST, adjuvant treatment, radiation therapy, and adjuvant hormonal therapy differed significantly among subgroups.

The median RFS and OS for all patients was 19.2 and 33.2 months, respectively. In multivariate analysis, BMI, ER status, lymphatic invasion, radiation therapy, and pCR rate were associated with RFS, and ER status, vascular invasion, radiation therapy, and pCR rate were associated with OS. Except in the ER+HER2− group, pCR was associated with better prognosis compared to non-pCR. Adjuvant hormonal therapy improved RFS both in ER+HER2+ and ER+HER2− groups, but did not improve OS in the ER+HER2+ group. Among 209 patients with HER2+ IBC, 134 received HER2 targeting therapies in neoadjuvant or adjuvant chemotherapy, and had a trend to improvement in RFS compared to chemotherapy alone (p = 0.082). The ER-HER2− group showed poorest outcome compared to other subgroups (P &lt; 0.001).

Conclusions: Sensitivity to NST differs depending on the ER and HER2 status in IBC pts. pCR rates based on these subgroups appear to be low. There is a need more effective treatments in the neoadjuvant and adjuvant therapies for all subgroups of IBC.

Multifocality and multicentricity in breast cancer and survival outcomes

BACKGROUND

The clinicopathological characteristics and the prognostic significance of multifocal (MF) and multicentric (MC) breast cancers are not well established.

PATIENTS AND METHODS

MF and MC were defined as more than one lesion in the same quadrant or in separate quadrants, respectively. The Kaplan-Meier product limit was used to calculate recurrence-free survival (RFS), breast cancer-specific survival (BCSS), and overall survival (OS). Cox proportional hazards models were fit to determine independent associations of MF/MC disease with survival outcomes.

RESULTS

Of 3924 patients, 942 (24%) had MF (n = 695) or MC (n = 247) disease. MF/MC disease was associated with higher T stages (T2: 26% versus 21.6%; T3: 7.4% versus 2.3%, P < 0.001), grade 3 disease (44% versus 38.2%, P < 0.001), lymphovascular invasion (26.2% versus 19.3%, P < 0.001), and lymph node metastases (43.1% versus 27.3%, P < 0.001). MC, but not MF, breast cancers were associated with a worse 5-year RFS (90% versus 95%, P = 0.02) and BCSS (95% versus 97%, P = 0.01). Multivariate analysis shows that MF or MC did not have an independent impact on RFS, BCSS, or OS.

CONCLUSIONS

MF/MC breast cancers were associated with poor prognostic factors, but were not independent predictors of worse survival outcomes. Our findings support the current TNM staging system of using the diameter of the largest lesion to assign T stage.

Ki67 expression in the primary tumor predicts for clinical benefit and time to progression on first-line endocrine therapy in estrogen receptor-positive metastatic breast cancer

We examined whether baseline Ki67 expression in estrogen receptor-positive (ER+) primary breast cancer correlates with clinical benefit and time to progression on first-line endocrine therapy and survival in metastatic disease. Ki67 values and outcome information were retrieved from a prospectively maintained clinical database and validated against the medical records; 241 patients with metastatic breast cancer were included--who had ER+ primary cancer with known Ki67 expression level--and received first-line endocrine therapy for metastatic disease. Patients were assigned to low (<10 %), intermediate (10-25 %), or high (>25 %) Ki67 expression groups. Kaplan-Meier survival curves were plotted and multivariate analysis was performed to assess association between clinical and immunohistochemical variables and outcome. The clinical benefit rates were 81, 65, and 55 % in the low (n = 32), intermediate (n = 103), and high (n = 106) Ki67 expression groups (P = 0.001). The median times to progression on first-line endocrine therapy were 20.3 (95 % CI, 17.5-38.5), 10.8 (95 % CI, 8.9-18.8), and 8 (95 % CI, 6.1-11.1) months, respectively (P = 0.0002). The median survival times after diagnosis of metastatic disease were also longer for the low/intermediate compared to the high Ki67 group, 52 versus 30 months (P < 0.0001). In multivariate analysis, high Ki67 expression in the primary tumor remained an independent adverse prognostic factor in metastatic disease (P = 0.001). Low Ki67 expression in the primary tumor is associated with higher clinical benefit and longer time to progression on first-line endocrine therapy and longer survival after metastatic recurrence.

P2-12-06: Nomogram To Predict Subsequent Bone Metastasis in Patients with Non Metastatic Breast Carcinomas

Background

Bone metastasis (BM) is one of the most common sites of distant metastasis for breast cancer. We hypothesized that its occurrence can be predicted if a clinical nomogram can be developed, thus allowing for selection of patients at high risk for BM.

Patients and Methods

Medical records of patients with non metastatic breast cancer were prospectively collected for the period between January 1997 and February 2007 at the M.D. Anderson Cancer Center (Texas, USA). A multivariate logistic regression analysis of selected prognostic features was done. Based on Cox proportional hazards regression model, a nomogram to predict BM was constructed and validated in an independent cohort of 579 patients with non metastatic breast cancer at time of diagnosis treated at the Tenon Hospital (Paris, France) between January 2003 and December 2005.

Results: Of 4175 patients with non metastatic breast cancer, 314 developed subsequent BM. Age, T stage, lymph node status, lymphovascular space invasion, breast cancer molecular subtype, adjuvant hormonotherapy were significantly and independently associated with subsequent BM. The nomogram had a concordance index of 0.69 (95% CI, 0.68 to 0.70) in the training set. The validation set showed a good discrimination with a concordance index of 0.65 (95% CI, 0.57 to 0.72). At 3, 5 and 7 years, the nomogram was well calibrated.

Conclusion: We have developed a robust tool that is able to predict subsequent BM in patients with non metastatic breast cancer. Selection of an enriched patient population at high risk for BM will allow to practice individualized therapeutic strategies, an adapted medical supervision and will facilitate the design of trials aiming at its prevention with the use of biphosphonate treatment.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P2-12-06.

Comparison of assay methods for detection of circulating tumor cells in metastatic breast cancer: AdnaGen AdnaTest BreastCancer Select/Detect™ versus Veridex CellSearch™ system

The detection of CTCs prior to and during therapy is an independent and strong prognostic marker, and it is predictive of poor treatment outcome. A major challenge is that different technologies are available for isolation and characterization of CTCs in peripheral blood (PB). We compare the CellSearch system and AdnaTest BreastCancer Select/Detect, to evaluate the extent that these assays differ in their ability to detect CTCs in the PB of MBC patients. CTCs in 7.5 ml of PB were isolated and enumerated using the CellSearch, before new treatment. Two cutoff values of ≥2 and ≥5 CTCs/7.5 ml were used. AdnaTest requires 5 ml of PB to detect gene transcripts of tumor markers (GA733-2, MUC-1, and HER2) by RT-PCR. AdnaTest was scored positive if ≥1 of the transcript PCR products for the 3 markers were detected at a concentration ≥0.15 ng/μl. A total of 55 MBC patients were enrolled. 26 (47%) patients were positive for CTCs by the CellSearch (≥2 cutoff), while 20 (36%) were positive (≥5 cutoff). AdnaTest was positive in 29 (53%) with the individual markers being positive in 18% (GA733-2), 44% (MUC-1), and 35% (HER2). Overall positive agreement was 73% for CTC≥2 and 69% for CTC≥5. These preliminary data suggest that the AdnaTest has equivalent sensitivity to that of the CellSearch system in detecting 2 or more CTCs. While there is concordance between these 2 methods, the AdnaTest complements the CellSearch system by improving the overall CTC detection rate and permitting the assessment of genomic markers in CTCs.

Results from a low-energy analysis of the CDMS II germanium data

We report results from a reanalysis of data from the Cryogenic Dark Matter Search (CDMS II) experiment at the Soudan Underground Laboratory. Data taken between October 2006 and September 2008 using eight germanium detectors are reanalyzed with a lowered, 2 keV recoil-energy threshold, to give increased sensitivity to interactions from weakly interacting massive particles (WIMPs) with masses below ∼10  GeV/c(2). This analysis provides stronger constraints than previous CDMS II results for WIMP masses below 9  GeV/c(2) and excludes parameter space associated with possible low-mass WIMP signals from the DAMA/LIBRA and CoGeNT experiments.

In vitro activity of doripenem and other carbapenems against contemporary Gram-negative pathogens isolated from hospitalised patients in the Asia-Pacific region: results of the COMPACT Asia-Pacific Study

The Comparative Activity of Carbapenems Testing (COMPACT) Study was designed to determine the in vitro potency of doripenem compared with imipenem and meropenem against a large number of contemporary Gram-negative pathogens from more than 100 centres across Europe and the Asia-Pacific region and to assess the reliability of Etest methodology for doripenem minimum inhibitory concentration (MIC) determination against these pathogens. Data from eight countries within the Asia-Pacific region, which collected 1612 bacterial isolates, are presented here. Etest methodology was found to be a reliable method for MIC determination. Doripenem showed in vitro activity similar to or better than meropenem and at least four-fold better than imipenem against Enterobacteriaceae. Against Pseudomonas aeruginosa, doripenem was also the most active of the three carbapenems in vitro. However, in vitro results do not necessarily correlate with clinical outcome.

Magnetostrictive Composite Material Systems Analytical/Experimental

Experimental and theoretical results are presented for a composite magnetostrictive material system. This material system contains Terfenol-D particles blended with a binder resin and cured in the presence of a magnetic field to form a 1–3 composite. Test data indicates that the magnetostrictive material can be preloaded in-situ with the binder matrix resulting in orientation of domains that facilitate strain responses comparable to monolithic Terfenol-D. Two constitutive equations for the monolithic material are described and a concentric cylinders model is used to predict the response of the composite structure. Experimental data obtained from the composite systems coincide with the analytical models within 10%. Particle size, resin system, and volume fraction are shown to significantly influence the response of the fabricated composite system.

Abstract P1-11-22: Bisphosphonates and Pathologic Complete Response to Neoadjuvant Chemotherapy in Patients with Breast Cancer

Purpose: Several studies have suggested that bisphosphonates have antitumor effects and that their use may have a potential benefit on recurrence and survival in patients with primary breast cancer. In a retrospective study, we sought to evaluate whether the use of bisphosphonates increased the rates of pathological complete response (pCR) in breast cancer patients receiving taxane and anthracycline-based neoadjuvant chemotherapy. Methods: We identified from our database 1449 breast cancer patients receiving taxane and anthracycline-based neoadjuvant chemotherapy between 1995 and 2007 at M.D. Anderson Cancer Center. Among the entire cohort, we identified by chart review those patients that while receiving chemotherapy also received bisphosphonates for a different indication (osteopenia or osteoporosis). Primary outcome was the proportion of patients achieving a pCR. Groups were compared using the chi-squared test. A multivariable logistic regression model was fit to examine the relationship between the use of bisphosphonates and pCR. An exploratory survival analysis using the Kaplan-Meier method was performed; groups were compared using the log-rank test.

Results: From the 1449 patients included, 39 (2.7%) received bisphosphonates at the time of neoadjuvant chemotherapy.66.7% received alendronate, 28.2% risedronate and 5.1% ibandronate. Those receiving bisphosphonates were older (P&lt;.001) and less likely to be obese (P=.04). The pCR rate was 26% in the bisphosphonate group and 16% in the non- bisphosphonate group (P=.11). After adjusting for potential confounding variables, patients treated with bisphosphonates tended to have higher rates of pCR (OR 2.16 95% CI 0.89-5.25); however the difference did not reach statistical significance. With a median follow up of 55 months (3-145) there were 412 recurrences and 359 deaths. There were no differences on 5-year PFS (71% vs 80%; P=.28) or 5-year OS (77% vs 82%; P=.42) between the two groups.

Conclusions: In this cohort of patients, the concurrent use of bisphosphonates at the time of neoadjuvant chemotherapy was not associated with significant increased rates of pCR. The observed estimates suggest a positive effect; however, it is possible that the small proportion of patients receiving bisphosphonates affected the power to detect a statistically significant difference. To fully test the hypothesis, additional, well-powered prospective studies to evaluate the potential use of bisphosphonates as antitumor agents used in the neoadjuvant setting are warranted.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P1-11-22.

Gene expression array testing of FFPE archival breast tumor samples: an optimized protocol for WG-DASL sample preparation

Archived formalin-fixed, paraffin embedded (FFPE) tissues constitute a vast, well-annotated, but underexploited resource for the molecular study of cancer progression, largely because degradation, chemical modification, and cross-linking, render FFPE RNA a suboptimal substrate for conventional analytical methods. We report here a modified protocol for RNA extraction from FFPE tissues which maximized the success rate (with 100% of samples) in the expression profiling of a set of 60 breast cancer samples on the WG-DASL platform; yielding data of sufficient quality such that in hierarchical clustering (a) 12/12 (100%) replicates correctly identified their respective counterparts, with a high self-correlation (r = 0.979), and (b) the overall sample set grouped with high specificity into ER+ (38/40; 95%) and ER- (18/20; 90%) subtypes. These results indicate that a large fraction of decade-old FFPE samples, of diverse institutional origins and processing histories, can yield RNA suitable for gene expression profiling experiments.